Reference Guide

Intermediate System to Intermediate System (IS-IS) | 915
graceful-restart ietf
e
Enable Graceful Restart on an IS-IS router.
Syntax
graceful-restart ietf
To return to the default, use the no graceful-restart ietf command.
Parameters
Defaults
Default is Graceful Restart disabled.
Command Modes
ROUTER ISIS
Command
History
Usage
Information
A Restart TLV included in every Graceful Restart enabled router’s HELLO PDUs. This enables the
(re)starting as well as the existing ISIS peers to detect the GR capability of the routers on the connected
network. A flag in the Restart TLV contains Restart Request (RR), Restart Acknowledge (RA) and
Suppress Adjacency Advertisement (SA) bit flags.
The ISIS Graceful Restart enabled router can co-exist in mixed topologies where some routers are
Graceful Restart enabled and others are not. For neighbors that are not Graceful Restart enabled, the
restarting router brings up the adjacency per the usual methods.
graceful-restart interval
e
Set the Graceful Restart grace period, the time during which all Graceful Restart attempts are
prevented.
Syntax
graceful-restart interval minutes
To return to the default, use the no graceful-restart interval command.
Parameters
Defaults
5 minutes
Command Modes
ROUTER ISIS
Command
History
ietf Enter ietf to enable Graceful Restart on the IS-IS router.
Version 8.3.19.0 Introduced on S4820T
Version 8.3.12.0 Introduced on S4810
Version 8.3.1.0 Introduced on the E-Series
minutes
Range: 1-20 minutes
Default: 5 minutes
Version 8.3.19.0 Introduced on S4820T
Version 8.3.12.0 Introduced on S4810
Version 8.3.1.0 Introduced on the E-Series